The present invention relates to an ultrasound diagnostic apparatus which determines a time intensity curve about a region of interest set to an ultrasound image.
A contrast agent may be injected into a body of a subject using, for example, an ultrasound diagnostic apparatus to perform imaging. Upon inspection using such a contrast agent, an inspection using a time intensity curve (TIC) may be carried out. The time intensity curve indicates a time change in the average pixel value in a region of interest (ROI) set onto an ultrasound image. Displaying the time intensity curve makes it possible to observe a change in the concentration of the contrast agent and diagnose the presence or absence of a disease in the subject or the degree thereof. There has been proposed in Japanese Unexamined Patent Publication No. 2010-075586 an invention in which when blood vessels are also included in a ROI in addition to a region target for observation of a time intensity curve, only a contrast agent penetrated into the region is observed using the time intensity curve except for a contrast agent that flows into the blood vessels.
In the related art, however, an artifact (virtual image) may exist in each ultrasound image acquired with time. As one example of the artifact, there is known a high intensity image. The high intensity image is generated from the motion of the subject or the motion of the heart close to the liver. Some or all of an area for the ultrasound image are brought to a high intensity. A problem arises in that a time intensity curve generated from a series of acquired images including such a high intensity image represents a false result according to a method of performing curve smoothing processing. Although a time intensity curve may be generated after a high intensity image has manually been eliminated in the related art ultrasound diagnostic apparatus, a problem arises in that it takes time for an operator to do the work of finding out a high intensity image and removing it.
It is desirable that the problems described previously are solved.